WIRELESS COMMUNICATIONS DIVISION
For additional information and latest specifications, see our website: www.triquint.com
1
V
CC1
RF
IN
V
REF
V
CC2
RF
OUT
GND
Bias Control
Match
Match
V
CTRL
GND
GND
GND
Product Description:
The TQM7638 is a 3V, 3 stage SiGe HBT Power Amplifier Module designed for use in
mobile phones. Its extremely small 4x4mm package makes it ideal for today's
extremely small data enabled phones. Its RF performance meets the requirements for
products designed to IS-95/98 standards. The TQM7638 provides the capability to be
operated in one, two, or continuous quiescent current modes. In digital quiescent
current mode operation, the TQM7638 is controlled from the base-band processor
using a CMOS compatible I
CQ
control voltage. Overall current consumption of the
device is minimized by selecting the lowest I
CQ
state available for each power output
level. RF input and output matching is included within the module; therefore, minimal
external circuitry is required.
The TQM7638 gives excellent RF performance with low current consumption resulting
in longer talk times in portable applications. The small 6mm square surface mount
package is ideal for new generation small and light phones.
Electrical Specifications:
Parameter
Min
Typ
Max
Units
Frequency
1850
1910
MHz
CDMA mode Pout
1
28
dBm
CDMA Mode Efficiency
1
31
%
Note 1:
Test Conditions CDMA Mode: V
CC1
=3.4VDC, V
CC2
=3.4VDC, V
REF
=2.90VDC, V
CTRL
=0.5VDC,
Tc=25C, Pout = 28.0dBm
TQM7638
DATA SHEET
3V HBT SiGe PCS Band
CDMA 4x4mm POWER
AMPLIFIER MODULE
Features
Analog continuous bias capability with
excellen linearity over 1.9 to 3.0VDC and
temperature stability over 30C to 85C
Excellent PAE
Small 10 pin 4x4mm module
1xRTT Compatible
Industry compatible digital quiescent current
state control
Analog continuous bias capability
CMOS compatible logic input
Internally matched input and output
Full ESD Protection
Low leakage current
Applications
Tri Mode CDMA phones
PCS Band CDMA based mobile phones
TQM7638 - Preliminary
Data Sheet
2
For additional information and latest specifications, see our website: www.triquint.com
Absolute Maximum Ratings
Symbol
Parameter
Absolute Maximum
Value
Units
V
CC1,
V
CC2
Power Supply Voltage, no RF Applied
RF Applied
-0.5 to 6.0
-0.5 to 5.0
VDC
V
REF
, V
CTRL
Bias reference voltages (V
REF
) and bias control voltage (V
CTRL
).
-0.5 to 5.0
VDC
P
DISS
Power Dissipation
2.5
W
T
C
Case Temperature, Survival
-40 to +100
C
T
STG
Storage Temperature
-40 to +150
C
RF
IN
DC Grounded RF input, 50ohm RF impedance
0 to 0V
VDC
RF
OUT
DC Blocked RF output, 50 ohm RF impedance
-20V to 20V
VDC
Note: The part may not survive all maximums applied simultaneously.
CDMA Mode Electrical Characteristics
1,2,3
Parameter
Conditions
Min.
Typ/Nom
Max.
Units
RF Frequency
1850
1910
MHz
Pout, I
CQ
-hi
V
CTRL
= low
28
dBm
Large Signal Gain, I
CQ
-hi
Pout = 28dBm, V
CTRL
= low
29
dB
Large Signal Gain, I
CQ
-low
Pout = 15dBm, V
CTRL
= high
26
dB
Gain Variation vs. Temp.
-30 to 85 C, Pout=28dBm
+/-2.5
dB
Quiescent Current, I
CQ
-hi
V
CTRL
= low
124
mA
Quiescent Current, I
CQ
-low
V
CTRL
= high
82
mA
Icc
Pout = 28dBm, V
CTRL
= low
607
mA
Power Added Efficiency
Pout = 28dBm, V
CTRL
= low
31
%
Adjacent Channel Power (ACP)
Pout = 28dBm, V
CTRL
= low, IS-95 Standard
-49
-
dBc
Alternate Channel Power (ALT)
Pout = 28dBm, V
CTRL
= low, IS-95 Standard
-58
dBc
Output Power Low-Power Icq state
ACPR=-47dBc, V
CTRL
= high, IS-95 Standard
15
dBm
Preliminary - TQM7638
Data Sheet
For additional information and latest specifications, see our website: www.triquint.com
3
CDMA Mode Electrical Characteristics
1,2,3
(cont'd)
Noise Power in Rx band
Pout=28dBm, V
CTRL
= low, IS-95 Standard
-88
dBm/30KHz
Input VSWR
Both I
CQ
-hi & I
CQ
-low
2:1
Second Harmonic
Pout=+28dBm, V
CTRL
= low, IS-95 Standard
<-35
dBc
Third Harmonic
Pout=+28dBm, V
CTRL
= low, IS-95 Standard
<-45
dBc
Recommended Supply Voltage
3.2
3.4
4.2
VDC
Reference Voltage
2.85
2.9
2.95
VDC
V
REF
Current, I
CQ
-hi
Hi-Power Mode, V
CTRL
= low
14
mA
V
REF
Current, I
CQ
-low
Low-Power Mode, V
CTRL
= high
6
mA
Leakage Current
V
CTRL
= low, V
REF
=0VDC
10
A
Logic Current (V
CTRL
)
100
A
Logic Voltage (V
CTRL
)
High
Low
1.7
0
2.0
0.25
3.5
0.5
VDC
VDC
Recommended Operating Temperature
-30
+85C
Ruggedness
No Damage, Pout=+28dBm, V
CTRL
= low, IS-95
Standard
10:1
Stability
No Oscillations, Pout=+28dBm, V
CTRL
= low, IS-
95 Standard
10:1
Note 1: Test Conditions: V
CC1
=3.4VDC, V
CC2
=3.4VDC, V
REF
=2.90VDC, V
CTRL
=0.5VDC, RF=1880MHz, T
C
= 25
C unless otherwise specified.
Note 2: Min./Max. limits are at +25
C case temperature unless otherwise specified.
Note 3: TriQuint Test Board.
TQM7638 - Preliminary
Data Sheet
4
For additional information and latest specifications, see our website: www.triquint.com
Application/Test Circuit:
RFin
RFout
V
CC1
RF
IN
V
REF
V
CC2
RF
OUT
GND
V
CTRL
J1
J2
TQM7638
GND
GND
GND
V
CC2
C4
C2
V
CTRL
C5
C6
V
REF
C1
V
REF
V
CC1
C3
U.S. PCS Band, 1850 - 1910 MHz
Bill of Material for TQM7638 Power Amplifier Module Application/Test Circuit*
Component
Reference
Designator
Part
Number
Value,
Cellular Band
Size
Power Amplifier Module
TQM7638
8pin/6mm square
RF Connector
J1, J2
Capacitor
C3
100pF
0402
Capacitor
C3, C4, C5, C6
0.1
F
0402
Capacitor
C1, C2
10
F
1210
*May vary due to printed circuit board layout and material
Preliminary - TQM7638
Data Sheet
For additional information and latest specifications, see our website: www.triquint.com
5
Product Description:
The TQM7638 is a three stage SiGe HBT power amplifier module
in a cascade configuration intended for use in CDMA PCS band
transmit paths.
Operation
The operation modes of the TQM7638 are determined based on
the setting of V
CNTRL
and V
REF
. The truth table below defines the
operating mode. Also, If the TQM7638 will be used in continuous
bias mode V
CNTRL
must be connected on the circuit board to
ground.
Operating
Mode
V
CNTRL
V
REF
High Power
Low
>2.7VDC
Low-Power
High
>2.7VDC
Continuous
Bias
Gnd
~1.9 to
3.0VDC
Off
Low
0VDC
Application
The applications circuit for the TQM7638 is very simple since most
of the critical components are included inside the module. There
are several important considerations when using the module in a
phone design.
First of all, it is important that the source impedance of the V
CC
power supply be very low. This is because the high current
demand during the modulation peaks of the CDMA waveform can
introduce voltage ripple at the symbol rate that will introduce
additional inter-modulation distortion or Adjacent Channel Power
distortion at the output of the power amplifier. If the power
amplifier has a quiescent current of 100 mA and a peak current
demand in excess of 1 amp, it is possible to see 900 mA change
in the current required from V
CC
as the modulated signal moves
from one extreme to the other. If the power supply source
impedance were 1 ohm, the resulting voltage ripple would be 0.9
volts which would cause the amplifier to fail it ACP requirements.
Generally, the power supply source impedance should be kept as
low as possible, preferably below 0.1 ohms total. Most battery
technologies used in cellular telephones will support a low source
impedance, but it may be necessary to supplement this in some
designs with an low ESR capacitor. Ceramic or tantalum
capacitors of approximately 10 micro-farads work well for this
requirement.
The application circuit includes 0.1
F capacitors at the PA control
line and V
CC
lines to ensure proper RF bypassing. Depending on
the phone board layout and circuit bypassing in other areas of the
phone, some of these components may not be necessary. There
are a number of VCO signals and IF signals used in a given
phone design, so it is important to protect the PA module from
interfering signals and to limit any interference coming from the
PA itself. Care should be taken when removing any of the RF
bypassing components.
One final area of concern is with excessive bypassing. If too large
a value of bypassing capacitor is used on the control line, it could
reduce the frequency response of the control line to the point
where a specification failure could occur. Please be sure that the
logic line and regulated supply lines driving the power amplifier
control lines are adequate to supply peak current requirements of
the bypassing capacitors chosen on the control lines.
One Bias State Operation
The TQM7638 can be operated using one bias state. If this mode
is selected, V
CNTRL
should be connected to ground.
Continuous Bias State Operation
The TQM7638 can be operated in continuous bias mode in which
the V
REF
voltage is varied from ~1.9V to 3.0V to set the PAM
quiescent current as appropriate for the desired output power
level. In this mode, V
CNTRL
should be connected to ground on the
phone board. Specific application circuit information for this mode
is available upon request.
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